Epoxy resin, method for producing same and use thereof

Abstract

An object of the present invention is to provide a multifunctional epoxy resin that is in a liquid state and that has a multifunctional structure. The multifunctional epoxy resin can be used as a reactive diluent and also used for a wide range of applications such as a molding material, a casting material, a laminating material, a paint, an adhesive, and a resist. The epoxy resin of the present invention is produced by glycidylation of dipentaerythritol represented by formula (1): wherein, in the number of moles of a hexafunctional compound (HG) and the number of moles of a pentafunctional compound (LG) in the epoxy resin, the ratio of the number of moles of (HG) to the total number of moles of (HG) and (LG), namely HG/(HG+LG), is in the range of 0.05 to 0.9.

1 . An epoxy resin produced by glycidylation of dipentaerythritol represented by formula ( 1 ): 
     
       
         
         
             
             
         
       
       comprising a hexafunctional compound (HG) and a pentafunctional compound (LG), the ratio of the number of moles of (HG) to the total number of moles of (HG) and (LG), namely HG/(HG+LG), is in the range of 0.05 to 0.9 in the epoxy resin. 
     
   
   
       2 . The epoxy resin according to  claim 1 , wherein the epoxy equivalent of the epoxy resin is in the range of 100 to 150 g/eq. 
   
   
       3 . A method of producing an epoxy resin comprising allowing dipentaerythritol represented by formula ( 1 ): 
     
       
         
         
             
             
         
       
       to react with an epihalohydrin in the presence of an alkali metal hydroxide, wherein at least one compound selected from the group consisting of aprotic polar solvents, quaternary ammonium salts, and quaternary phosphonium salts is used as a reaction activator. 
     
   
   
       4 . The method of producing an epoxy resin according to  claim 3 , wherein the reaction activator is an aprotic polar solvent, the ratio of the epihalohydrin to the aprotic polar solvent satisfies 0.5≦(epihalohydrin)/(aprotic polar solvent)≦4, and the reaction temperature is 40° C. or higher. 
   
   
       5 . The method of producing an epoxy resin according to  claim 3 , wherein the reaction activator is selected from the group consisting of a quaternary ammonium salt and a quaternary phosphonium salt, and a secondary or tertiary alcohol is used as a reaction solvent. 
   
   
       6 . An epoxy resin composition comprising the epoxy resin according to  claim 1  and a curing agent. 
   
   
       7 . A cured product produced by curing the epoxy resin composition according to  claim 6 . 
   
   
       8 . An epoxy resin composition comprising the epoxy resin according to  claim 2  and a curing agent. 
   
   
       9 . A cured product produced by curing the epoxy resin composition according to  claim 8 .